Projectile



[ Dec. 16,, 1924.

N G R E EN PPPPP CT WELL ILE

2 NNNNNN 0R Patented Dec. 16, 1924.

UNITD STATES PATENT ()FFICE.

NEVIL GREENWELL, OF BETHLEHEI/I, PENNSYLVANIA, ASSIGNOR TO BETHLEHEMSTEEL COMPANY.

PROJECTILE.

Application filed February 5, 1924. Serial No. 690,741.

To all whom it may concern:

Be it known that I, NEVIL GnEnNwELL, a citizen of the United States,residing at Bethlehem, county of Northampton, and State of Pennsylvania,have invented a new and useful Improvement in Projectiles, of which thefollowing is a full, clear, and exact description, reference being hadto the accompanying drawings, which form a part of this specification.

The present invention relates to improvements in armor piercingprojectiles. In practice it has been found heretofore that inpenetrating armor obliquely, the cavity wall of the shell adjacent thebase thereof is frequently ruptured. It is the principal aim of thepresent invention to produce an armor piercing projectile which willpenetrate modern armor on oblique impact without rupture of the cavitywall, and at the same time none of the ballistic properties shall besacrificed.

To these ends the projectile may be constructed so that parts adjacentthe base end thereof are adapted to be removed or sheared off whenpenetrating the armor, thereby reducing the diameter of the body of theprojectile adjacent said end.

It is recognized by those versed in the ordnance ballistic art thatirregularities to the exterior surface of the projectile should beavoided as much as possible and it is the object of this invention toprovide a projectile having a. weakened base portion and at the sametime conform to standard design wherein the exterior cylindrical surfaceat the rear of the rotating band is uninterrupted. It should beunderstood that the method usually employed to assemble the rotatingbands in a groove cutin the cylindrical surface of the projectile andadjacent the base thereof, is to provide a ring of copper. of uniformthickness, having an internal diameter less than the exterior diameterof the projectile, to eX- pand the ring by heat until the expansion ofthe ring is sufficient to allow same to be slipped over the projectilecontiguous with said groove. The band is then placed in dies under apress and the ring is pressed into its seat under great pressure and thecopper flows and contacts firmly with the walls of its seat. Then theband is ma- 'chined exteriorly to the desired profile. This method ofapplying bands to projectiles not only seats the bands firmly in placebut also toughens the copper materially and makes it homogeneous whichis very desirable.

The above described method of assembling bands to the projectile bodysubjects the walls of the band seat to high stresses and it is the mainobject of this invention to provide a projectile conforming to standardexterior contour having a frangible base and a band seat having integralwalls of solid construction.

My integral wall construction aforesaid further provides a substantialsupport for the rotating band when the latter engages the rifling of thegun from which the projectile is fired.

The preferred embodiments of the invention are shown in the accompanyingdrawing, in which Figure 1 is a side elevation of the projectile;

Figure 2 is a longitudinal part section, illustrating my preferred formof frangible base end;

Figure 3 is similar to Figure 2 and illustrates an alternate method ofattaching the base ring; and

Figure 4 is similar to Figure 2 and illustrates another embodiment of myinvention.

In the drawings, I show a projectile 10 having a rotating band 11fitting in a groove 12, formed in the body of the projectile. The

body 10 is reduced in diameter at the rear of the groove 12 from thebase to a shoulder 13 and forms with the wall ll a frangible collar 15.Preferably this latter collar should be only of sufficient thickness towithstand the pressure to which it is subjected when the rotating bandis being pressed firmly to its seat in the groove 12. Seated on thereduced portion of the body at the rear of the band is a ring 16 whichis attached to the body by a means which is sufficiently strong to allowfor rough handling in transportation but which is easily frangible whensubjected to such forces as may be encountered when the projectilepenetrates armor. In Figure 2 the frangible ring portion 16 of theprojectile is attached to the body portion by means of pins 17, while inFigure 3 the ring is attached by means of threaded engagement with thebody portion as at 18. In Figure l the ring is retained in position bybeing made integral with the base plug 19 which is a usual component ofa projectile of the armor piercing type. In the latter type offastening, a weakening groove 20 is provided to facilitate the fracturebetween the ring of the base plug proper so that the firm seating of theplug in the body is not disturbed when the projectile penetrates thearmorv In operation, when the projectile perforates the armor plateobliquely the projectile takes more or less a diagonal path and issubjected to high transverse stresses as the projectile tends to spin upa right angle to the surface of the plate and produce a normalperforation. This tending to right itself becomes intense as theprojectile emerges from the rear of the plate and the lateral stressimposed at the base before it emerges is so great that the rear end ofthe body would fracture and would most probably expose the projectilecavity, which is undesirable, were it not for the provision of thefrangible collar 15 and the detachable ring portion 16, which areimmediately sheared off the body proper which continues its flightessentially intact until exploded by the usual means provided.

Having now fully described my invention, what I claim and desire. toprotect by Letters Patent is:

1. A projectile comprising a shell body having a band seat and a reducedportion disposed rearwardly of the seat, a frangible collar separatingthe seat from the reduced portion, a band in the seat, a filler ring onthe reduced portion, and a frangible connection between the filler ringand said body.

2. A projectile comprising a shell body having a band seat and a reducedportion disposed rearwardly of the seat, a frangible collar integralwith said body separating the seat from the reduced portion, band in theseat, a filler ring on the reduced portion, and a frangible connectionbetween the filler ring and said body.

3. A projectile comprising a shell body having aband seat and a reducedportion disposed rearwardly of the seat, a band in the seat, a frangiblecollar separating the seat from the reduced portion, said collarconstituting the rear wall of said seat and being sufficiently rigid tosupport the band during the assembling step and frangible when subjectedto excessive forces, a filler ring mounted on the reduced portion, and afrangible connection between the ring and said body.

4. A projectile comprising a shell body having a band seat and a reducedportion disposed rearwardly of the seat, a frangible collar separatingthe seat from the reduced portion, a band in the seat, a plug threadedin the base opening of the projectile, a filler ring mounted on thereduced portion and projecting rearwardly from body co-planar with therear face of the plug and a frangible connection between the ring andthe plug.

5. A projectile comprising a shell body having a band seat, a band insaid seat, the body having a reduced portion disposed at the rear of theseat, a frangible collar sep arating the seat and the reduced portion tonormally support the rearward thrust of the band, a ring mounted on thereduced portion and abutting the rear face of said collar, said ringextending to the base of the pro jectile and having an external diametersubstantially the same as the outside diameter of the body, and afrangible connection between the ring and said body.

In testimony whereof I hereunto aflix my signature this 30th day ofJanuary 1924.

NEVIL GREENVVELL.

